SpaceX (general discussion)
- Thread starter FutureSpaceTourist
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Same reason a 747 or a C-5 doesn't have one.
Because it has an inherent intact abort capability over 99% of its flight envelope with an over 90% chance of success and decades of flight experience and data to back up that claim? Otherwise... No, not the reason.
The falacy that true 'commercial' space travel has to somehow meet aircraft safety standards, (or not and at least act like they do which is closer to the truth) is based on the historical similarity that aircraft have always met and exceeded railroad operational and safety regulations and is there for the same reason. It's NOT an airplane and no matter how much you want it to be it never will be. It won't have one because they aren't going to design one in and if it crashes and people die that's a price we pay for progress.
If you have an issue with that statement then that's on you because it's rather true and always has been with transportation but it also leads to heavier regulation and control down the line so your actual milage may vary. The problem with that stance though is that people tend to NOT be incentavized by a higher than they consider 'normal' chance of dying while being transported somewhere on a vehicle they paid to ride in. As space travel, let alone colonization are not yet common or econmical and there is not going to be as huge a demand as many assume even when it IS such an attitude may be counter-productive in the short run even though they can actually point to the differenence in air safety 75 years ago and today. It's not the same since space travel is and remains essentially the 'same' today as it was 50 years ago despite technical advancment it's STILL not as "safe" as flying in an airplane and likely won't be for a very long time.
Randy
And I'll note that the discussion on the effects of more LEO constellations is missing a point while focusing on astronomy...
To whit; You do realize that the more LEO constellations that are deployed, (and the DoD is planning one now through DARPA among others) the more controlled and restricted orbital access will have to become? Just something to think about
Randy
To whit; You do realize that the more LEO constellations that are deployed, (and the DoD is planning one now through DARPA among others) the more controlled and restricted orbital access will have to become? Just something to think about
Randy
It's been openly discussed before and while some like the idea they have no real means of enforcing it so the point tends to be moot
People who don't know/understand history and repetition and all that
Randy
Dilandu
I'm dissatisfied, which means, I exist.
With all respect, but if we are talking about a spaceship, any kind of abort capability is useful only on less than 1% of its "flight envelope".
Space travel will present unique safety challenges specific to its' environment. Nonetheless, there is already an analog to it today. It operates in an unforgiving and lethal medium and yet does not rely on escape pods or a separable structure.
In the world of nuclear submarines, design seeks to drive failure to the lowest possible level backed up by protocols to operate and maintain equipment with a culture that eliminates slipshod or incompetent behavior. It seems to have worked for over 50 years now.
Something similar to the "subsafe" process for design, maintenance, and operation of spacecraft will be needed. For launch and re-entry, the kinetic and thermal energies are so extreme, abort opportunities are limited. Autonomous operation and putting sensors everywhere to constantly analyze system performance for signs of anomalous behavior is a given.
Unfortunately, it would be a miracle if no serious accident occurs over time. But mandating architectures which only governments could afford effectively shuts down any idea of meaningful expansion in space development.
In the world of nuclear submarines, design seeks to drive failure to the lowest possible level backed up by protocols to operate and maintain equipment with a culture that eliminates slipshod or incompetent behavior. It seems to have worked for over 50 years now.
Something similar to the "subsafe" process for design, maintenance, and operation of spacecraft will be needed. For launch and re-entry, the kinetic and thermal energies are so extreme, abort opportunities are limited. Autonomous operation and putting sensors everywhere to constantly analyze system performance for signs of anomalous behavior is a given.
Unfortunately, it would be a miracle if no serious accident occurs over time. But mandating architectures which only governments could afford effectively shuts down any idea of meaningful expansion in space development.
Thanks but it's not that simple and it depends on the system and launch vehicle as well. Orion is aiming for 100% ascent coverage, (https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20140011918.pdf) but as the video notes there are always going to be spots you can't abort from. Also as noted Starship can possible prove it's 'safe-enough' but that's not clear yet and won't until it has a actual (and much deeper) flight history. It's SpaceX's decision to make.
I was specifically addressing the idea that it's as "safe" as an modern aircraft with over 100 years of a VERY steep in spots learning curve on aircraft safety. Space travel is technically a bit over 50 years on but in reality it's not that more advanced than it was at the start and while the average 'safety' is pretty high the consequences of an 'failure' can be catastrophic very easily. Starship is NOT as huge a technical leap ahead as some think. It's a launch vehicle with two stage, lots of moving and complicated parts and failure IS an option. It's obviously NOT going to be as 'safe' as a 747 or C5 because it doesn't have the history and depth of those aircraft's safety systems and operations.
The progression towards a safer system is pretty inherent in any transportation system as it evolves, but the evolution takes time and unfortunately quite often the learning curve can turn into a deadly cliff. SpaceX thinks they can balance the risk and benefits of not having an abort system and that's frankly their call. We'll see what happens but it's very likely it's going to go wrong at some point as the current level is still pretty early. As noted in the video you fix that by flying a LOT more, which I have no argument with
And even if some sort of 'abort' system is mandated it's not going to be something "only governments" can afford for pretty obvious reasons. If it's required designers and builders will find a way to do it and still make a profit, it's the nature of the process. Trying to excuse not having a safety system because you "can't afford it" is a really good way to get an even stricter set of regulations
In Starship's case there aren't a lot of "good" options because of the margins that will be inherent in the design much like the Shuttle and Buran. As the video noted if they ever get NASA or another government agency as a customer for people moving it's likely they will insist on something OR a pretty clear flight and safety history to base a risk assessment on. Quite obviously at this point Starship has neither and the possible failure modes are mostly assumptions from previous data from different vehicles.
One thing that bugged me about the video is he states that prior to SpaceX everyone thought propulsive landing was 'impossible' which is not at all true since it's been known to be possible since the beginning. Heck it was a primary demonstration goal of the DC-X program! The main issue was the need to restart rocket engines that early on weren't really conducive or easy to restart and the primary problem that holding propellant through the flight for that purpose will cost you payload and performance. There are also operational considerations since a lot depends on how you plan to land and what that entails. (Most assumed some ability to 'hover' and adjust the landing whereas, like New Sheppard, SpaceX thought outside the box and came up with the hover-slam. We're actually getting USED to it now and it will be used for Starship as well but THAT was what freaked most folks out the first couple of times
) That most LV's were expendable was also a major factor but it was seriously considered and studied several times on several different reusable systems.Oddly it was found that propulsive landing with a rocket engine wasn't really as effective as one might think but that some type of 'airbreathing' engine was more efficient and reliable. The main issue there was the mass of the engine compared to the propellant load to run a rocket for landing and that itself tended to be variable and arguable either way. And it's not that you actually need an entire 'engine' since you can often just use a tip turbine 'fan' system with the turbine run on air/fuel or even monopropellant/RCS. The main hurdle is finding a way to incorporate it into the design, especially as a retrofit. I can't see SpaceX using one on Starship simply because they are aiming for multi-planetary use and the atmosphere on Mars is to thin. But for an Earth orbital transport system it would make a lot of sense in some ways. Adding a 'ring-fan' around the top of the booster stage (somewhat similar to the aerodynamic ring on New Sheppard for example) could work. But again it's not a choice SpaceX is likely to make given the way they are going.
Randy
It's odd to think there may be enough politicians with a different understanding of risk/benefit to stay out of Spacex's way but I am willing to bet there is. And there is the added plus that it would be unpopular for them to act otherwise.
I am also willing to extend enough benefit of doubt to think a majority is also able to comprehend the long term eventuality of a major accident and can accept it as long as it was not caused by corrupt decision making or sloppy procedures. Of course, this doesn't take into account contrived media hyperventilating.
I am also willing to extend enough benefit of doubt to think a majority is also able to comprehend the long term eventuality of a major accident and can accept it as long as it was not caused by corrupt decision making or sloppy procedures. Of course, this doesn't take into account contrived media hyperventilating.
Dilandu
I'm dissatisfied, which means, I exist.
I mean, that 99% of spaceship flight is performed in the situation, where no cost-effective escape system could be of much use. For example, if you are coasting to Mars and suddenly found out that your engines are busted and could not perform a deceleration burn, there could be no escape system that would have enough delta-V to return you to Earth (unless you have a torchship, of course, with secondary engine system)
Not really a 'bet' since evidence suggests that's the general path at the moment. But we also known that public mood and therefore government oversight can change rapidly. It was a hands off attitude towards suborbital travel until Spaceship Two crashed then they demanded answers. You'd see something simlar with a Starship crash but frankly that's where SpaceX and Musk's media hype tend to work against them. Overall most of the political machine seems willing to let things slide. Of course we're runing into an election year and SLS is getting ready to fly so ...
That's not evident at all. The public is not really as invested as one might think in what SpaceX is currently up to care one way or another. This WOULD become an issue is people die and as you mention how the media "spins" it and the government runs with it will be the important thing. From past experiance the public will want rapid and easy "fixes" for the "problem" and the government will give it to them. Whether it's a 'good' fix is beside the point. If we're lucky SpaceX can work with the solution.
The public in general understands that accidents happen, having said that they also will want to be assured it won't happen again and that's where they want regulation and oversight. In essence while you and I (and others here) watched and understood the video the majority of people wouldn't and would require a distilled and simplified version. And then they will still want 'someone' to fix the problem and in this day and age it's not likely they will 'trust' SpaceX to do it.
Randy
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That's less of a system than part of the flight and operations planning. You don't plan a trajectory you can't do something about and in Starship's case the fact its planned to aerobrake at both ends is part of the 'safety system' design. The abort profiles we're actually talking about are more directed at ascent from Earth or Mars. Where you can and should have a way to handle such an event at least in theory. SpaceX has decided not to and that's again their decision to make.
Randy
NeilChapman
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It just hit me that SpaceX will likely double the number of operational satellites in orbit next year.
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SpaceX Is Lobbying Against Amazon's Internet-Beaming Satellites - Slashdot
An anonymous reader quotes a report from Motherboard: When Amazon confirmed it was planning to launch 3,236 broadband internet-beaming satellites into low-Earth orbit, much of the media reported it as if it were a done deal -- the latest, inevitable step in the corporation's quest to conquer...
tech.slashdot.org
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Click-bait title. SpaceX isn't against competition. They're against the fact that Amazon is trying to avoid a hoop everybody else had to jump through.
"Amazon requested a special waiver to FCC rules that would grant it the necessary permission. The problem, though, is that the FCC already handed out licenses to that spectrum years ago to nine other satellite internet companies in a different, more complicated process. Those companies -- including SpaceX and OneWeb -- are now lobbying the FCC to deny Amazon's waiver request, according to FCC records. If successful, they could significantly reduce Project Kuiper's viability in an already oversaturated market."
But it's always fashionable to attack SpaceX so. . .
"Amazon requested a special waiver to FCC rules that would grant it the necessary permission. The problem, though, is that the FCC already handed out licenses to that spectrum years ago to nine other satellite internet companies in a different, more complicated process. Those companies -- including SpaceX and OneWeb -- are now lobbying the FCC to deny Amazon's waiver request, according to FCC records. If successful, they could significantly reduce Project Kuiper's viability in an already oversaturated market."
But it's always fashionable to attack SpaceX so. . .
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Not in a SpaceX thread. That was a Boeing/ULA effort.
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"SpaceX teams across the United States are readying for what the company’s chief operating officer predicts will be a record number of launches in 2020.
Before the end of January, SpaceX aims to perform four Falcon 9 launches from Florida’s Space Coast — three for the company’s Starlink broadband network, and a crucial in-flight abort test for the Crew Dragon spacecraft no earlier than Jan. 11."
. . .
"“I think in 2020 we’ll do more, and that’s because of Starlink,” she said in a roundtable discussion with reporters earlier this month. “I think we will have 14 or 15 non-Starlink launches, and then we’ll fly Starlink as often as we can.
“I need second stages to be built a little bit faster, but we would probably shoot for 35 to 38 missions next year,” Shotwell said."
China, with the most, did 33 in 2019 (US at #2 did 27) for comparison.
FighterJock
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I for one look forward to more launches of the Falcon Heavy in 2020.
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There's just the one, at the end of 2020. (Which, if history is any indicator, means early 2021.
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FighterJock
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One Falcon heavy launch in 2020 and could slip into 2021? I would have thought that SpaceX would have used the Heavy a lot more often than that.
One Falcon heavy launch in 2020 and could slip into 2021? I would have thought that SpaceX would have used the Heavy a lot more often than that.
Falcon 9 capability grew quite a bit between Heavy development starting and Heavy flying. Many payloads that would have flown on Heavy were able to fly on F9 instead.
One Falcon heavy launch in 2020 and could slip into 2021? I would have thought that SpaceX would have used the Heavy a lot more often than that.
Falcon 9 capability grew quite a bit between Heavy development starting and Heavy flying. Many payloads that would have flown on Heavy were able to fly on F9 instead.
Yep. The payloads originally planned for the specs of Heavy when it was in development can mostly be launched with normal F9:s, and while new payloads that would make use of the extra upmass are under development, they will likely still take a few years.
Also, the Starlink/OneWeb/Kuiper boom kind of dropped the bottom out of the heavy geostationary commsat market, which was the primary possible customer of Heavy.
Spacex launch cadence ramping up in 2020.
https://spaceflightnow.com/2019/12/...nch-cadence-with-series-of-starlink-missions/
https://spaceflightnow.com/2019/12/...nch-cadence-with-series-of-starlink-missions/
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They can’t use it if they don’t have the customers for it. The only ones going forward seems to be the US government.One Falcon heavy launch in 2020 and could slip into 2021? I would have thought that SpaceX would have used the Heavy a lot more often than that.
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See post #2423 above.
Revamped SpaceX Crew Dragon Parachute Aces 10th Test in a Row (Photo)
That's the milestone Elon Musk had pegged as necessary before Crew Dragon can fly astronauts.
www.space.com
With the notable exceptions of Tresher and Scorpion, but your point actually stands, these two were unfortunate exceptions rather than ordinary business. The USN learned a lot from these two, and carried on, and no further accidents happened.
Just compare with Soviet submarines - very scary - accident rates.
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